If during the procedure of in vitro fertilization is possible to obtain more embryos than necessary for a transfer, you can save them at very low temperatures - spend the remaining embryo cryopreservation.
These embryos are property pair, and can be further used for the next attempt and the next pregnancy. The advantage of cryopreservation is that getting an extra chance, a woman avoids procedure of stimulation and follicle puncture and is preparing to transfer only. Before embryo transfer is performed ultrasound monitoring, as necessary, appoint support drug cycle.
If after stimulation of ovulation in women with follicle puncture was obtained several mature eggs, and in the future, these egg fertilized and the embryos were obtained good quality, those embryos that remained after replanting may be frozen. These frozen embryos can be used in cryo-program, for which there is no need to carry out ovulation stimulation, and do not need to re-puncture of the ovaries. Be stored frozen embryos as much time as is necessary - even decades. When stored at -196 ° C in liquid nitrogen stops the metabolic activity of cells.
Cryopreservation is a "biological support" for the couple: it is impossible to accurately predict whether a successful stimulation and fertilization at a possible next attempt. Retaining the remaining embryos, the couple increases your chances. Cryopreservation gives patients also some economic confidence - the cost of storing, thawing and embryo transfer is almost an order of magnitude lower than the "fresh" attempt in vitro.
Cryopreservation - a tried and tested method. No adverse effects on the fetus during pregnancy and associated with cryopreservation, is not revealed. The downside is the possible loss of embryos in the process of freezing and thawing - not all embryos remain viable, but in clinics with well-established technique of cryopreservation of embryos after thawing their survival is 70-80%.
vitrification of embryos
Vitrification - a super-fast method of freezing embryos.
Vitrification - a modern method of freezing cells, providing the highest level of survival after thawing due to the use of highly concentrated cryoprotectant, small amounts of media and the limited time required to freeze.
When the method of vitrification of cryoprotective solution, in which the embryos are, does not crystallize upon cooling, and immediately enters the glassy state. When using the same slow freezing microscopic ice crystals are formed, which does not exclude the possibility of injury to the cells of the embryo, which consists of 95% water. Consequently, the absence of crystal phase - a significant difference from the vitrification method of slow freezing, which is worse than the embryo transfer.
Vitrification of embryos carried by mutual desire of the couple.
After vitrification thaw embryo survival is about 85% and the developing embryos after thawing are no different from those obtained in a standard IVF cycle. The risk of any abnormalities and complications of this does not exceed that of the standard IVF procedure.